Rotary drilling tool for cable operation



Sept. 1, 1925.

A. S. BAPTIE ROTARY4 DRILLING TOOL FOR CABLE OPERATION Filed Jan. l1.1923 Mmm fallen? new and useful Rotary Drilling Tool forV Patented Sept.l, 1925.

ALBERT S. BAPTIE, OF LONG BEACH, CALIFORNIA.

ROTARY DRILLING TOOL FOR CABLE OPERATION.

Application led January 11, 1923. Serial 11b. 612,119.

To all whom it may concern:

Be itl known that I, ALBERTVS. Bnr'rm, a citizen of the United States,residing at Long Beach, in the county of Los Angeles -and State ofCalifornia, have invented a Cable Operation, of which the following is aspecification.

My invention relates to deep well drilling tools, and particularly torotary tools of this kind that are adapted for cable operation. Myobjects in the invention are, first, to provide practical means forrotating cable suspended drilling bits b the elfects of gravity; second,to afford acilities for combining churning and rotary drilling action ina single device; and, third, to produce a mechanism for this purposethat is adapted for use in connection with well casings of ordinarydimensions, and which is capable of under-cutting such casingsif'desired.

Other objects and advanta es of my construction will appear hereina er,and while I show herewith and will describe a preferred embodiment, Idesire tov be under stood that I do not limit myself to such embodiment,since various changes andV adaptations may be made therein withoutdeparting from the spirit of my invention as hereinafter claimed.

My objects are attained by means of the mechanism illustrated in theaccompanying drawing, in which- Figure 1 is an elevational view withoertain parts broken away and shown in central section.

Figure 2 is an enlarged sectional plan D heads.

Figure 3 is an enlarged sectional plan view taken on the line 3-3 ofFig. 1, illustrating diagrammatically the separate and combined drillingareas of the respective bits" employed.

Figures 4 and 5 are fragmentary elevations of opposite sides oftheactuatin bar of the mechanism, as viewed in the irection indicated byarrows 4 and 5 respectively.

Similar numerals refer to similar parts throughout the several views.

, In the form of my invention selected for illustrative purposes thehousing 6 is roughsomewhat smaller than the bore of the well 'casing inwhich it is to operate. It is interiorly provided with a horizontalperforate partition 7, near the top, and there are a pair of stulingboxes 8 at the bottom. There is also provided an interior axial guidevrod 9, ailxed to the housing in some suitable manner at the bottom, asby the reduced threaded end and nut 10.

A strong cover plate 11, with an integral upstanding axial tube portion12, is conveniently attached to the housin as by the cap screws 13.There is a st g box 14 at the upper end of tube portion 12, and thelower face of the cover plate is provided with surfaced bosses 15 toserve as thrust abutments for certain of the working parts to bedescribed later.

' Within tube 12, and stung box 14, the working stem 16 is adapted toreciprocate. At its upper end this stem carries the usual taper screwpin 17, by means of which the whole mechanism of my invention may besuspended from a drilling stem or cable .in the manner common to theart. At its lower end stem 16 screw-engages the actuating bar 18,4through-which rotary motion is imparted to the drill stems 19 and 20 ina -manner to be explained presently.

surfaces 4 and 5, parallel with its axis, and

these surfaces are helically grooved insuch a manner that in effect theyconstitute multi-threaded partial nuts adapted to engage the skew, orhelically cut, pinions 21 and 22 respectively. These respective pairs ofengaged helices are made right and left, so

- that longitudinal movement of the actuating bar imparts rotary motionto the pinions in opposite directions.

Pinions 21 and 22'are attached in some suitable manner, as b the screwpins 23, to the upper ends of rill stems 19 and 2) respectively,'so` asto be able to impart rotary motion to the latter as well as to supporttheir weight.' In order to accomplish the latter, as well as to resistthe upward thrust that results from the drilling opera-V tions, thepinions are provided with central finished bosses 24 and 25perpendicular to their axes. The upper of these re-act against bosses 15on the under surface of the cover plate, and the lower rest upon theupper end faces of the journal bushings 26 which are supported bypartition 7.

Drill stems 19 and 2O are adapted to rotate in bushings 26 and stuflingboxes 8. At their lower ends they have means Jfor attaching the rotarybits 27. The latter commonly are of the fish tail type as shown and,when the width of these is greater than the distance between the axes ofthe drill stems, means must be provided for attaching them in properangular relation to afford mutual clearance during rotation. The angularmeans of adjustment is not a part of the present invention, and anysuitable means may be employed. As illustrated the attachments comprisestraight shank screw and socket connections, as indicated by dottedlines at 28, and interposed shims 29 of proper thickness to allow thebit stocks to seat on their respective stems in the desired angularposition.

To overcome excessive operating shocks when the reciprocating partsreach the end of their travel, a heavy helical spring 30 surroundingstem 16 is provided at the top, and a similar spring 31, surroundingguide rod 9, is used at the bottom.

In operation the device is suitably sus pended from a drilling cable,and reciprocated vertically thereby, in the ordinary manner employed inchurn drilling. In the upper position of the cable the operating stemis'extended and the actuating bar is at the top of its stroke and mostlywithin tube portion 12. This disposition of the cooperating parts ismaintained until,on the downward throw of the cable, the bits strike thebottom of the drill hole, which arrests their downward motion. Theactuating bar,

impelled by its momentum and that of whatever drill rods and other partsare used above it, continues its downward movement, and in so doingcauses bits 27 to rotate oppositely as shown by the arrows of rotationin Figs. 2 and 3. This rotary movement of the bits may continue untilthe several parts are in the relative positions shown in Fig. 1. Thesucceeding upward movement of the cable reverses the rotation of thebits, and allows the operating stem and actuating bar to reach the upperend of their travel, while the whole device is being elevated to repeatthe operations just described.

The drilling effect resulting from the use of my device is a.combination of rotary and churn drill action. It is a chisel-edge impactwith a very strong rotary tendency accompanied by actual rotation wherethe nature of the ground permits. The backlash and twist of thesuspending cable insure that a constantly changing point of attack ispresented to the 'cutting edges of the bits.

Referring to Fig. 3, the dotted line 32 represents the outline of thehousing in plan;

retrasa circles 33 represent the rotary drilling areas of theirrespective bits; circle 34 is the area covered by the combined rotaryand churn drill action of the device considered as a whole; and circle35 indicates the minimum bore of the well casing in which the mechanismcan be operated. It will be noted that the diameter of circle 34,corresponding to the size of the hole that is being drilled, isconsiderably larger than the diameter of circle 35 representing the boreof the well casing. Consequently the device may be used to under-cut thecasing when desired.

To withdraw the mechanism from the drill hole, the bits must be broughtinto some such position as indicated by the dotted lines 36 of F ig. 3,so as to be contained wholly within the periphery of circle I desire topoint out that, if considered desirable, ratchet devices may beintroduced between pinions 21 and 22 and their respective bits. Thiswould enable the actuating bar to be elevated without turning the bitsbackward.

I also wish to say that the housing preferably should be partiallyoil-filled to insure continuous lubrication of the interior workingparts.

Having thus fully described my invention in a manner that will readilybe understood by those familiar with this art, I claim;

1. In combination with a cable adapted to reciprocate vertically; adrilling tool suspended from said cable comprising a pair of rotary bitshaving parallel axes spaced less than the cutting diameters of the bits;said tool being adapted for causing its bits to rotate by reciprocatingthe cable and, by twisting the cable during reciprocation, to change itsangular position in the drill hole for presenting new drilling areas tothe bits and causing the tool to drill a round hole of larger diameterthan the bits.

2. In combination with a cable adapted to reciprocate vertically; adrilling tool suspended from said cable comprising a pair of bitsadapted for rotation in opposite directions havingV parallel aXes spacedless than the cutting diameters of the bits; said tool being adapted forcausing its bits to rotate by reciprocating the cable and, by twistingthe cable during reciprocation, to change its angular position in thedrill hole for presenting new drilling areas to the bits and causingt-he tool to drill. a round hole of larger diameter than the bits.

3. In combination with a cable adapted to reciprocate vertically; a.drilling tool suspended from said cable comprising a pair of bitsadapted for rotation in opposite directions by gravitational descent ofcooperating parts; 4said bits having parallel axes spaced less thantheir cutting diameters; said tool being adapted for causing its bits4to rotate by ,reciprocating the cable and, by

twisting the cable during reciprocation, to change its angular positionin the drill hole for presenting new drilling areas to the bits andcausing the tool to drill a round hole of larger diameter than the bits;

4. In combination with a cable adapted to reciprocate vertically; adrilling tool suspended from said cable comprising a pair of fiat bitsadapted for rotation in opposite directions by gravitational descent ofcooperating parts; said bits having parallel axes spaced less than theircutting diameters and means for preventing mutual interference of theircutting blades; said tool being adapted for causing its bits to rotateby reciprocating the cable and, by twisting the cable duringreciprocation, to change its angular position in the drill hole forpresenting new 2G drilling areas to the bits and causing the tool todrill a round hole of larger diameter than the bits.

5. In combination with a cable adapted to reciprocate vertically; adrilling tool suspended from said cable comprising a pair of flat bitsadapted for rotation in opposite directions by gravitational descent ofcooperating parts; ysaid bits having parallel axes spaced less thantheir cutting diameters and being gear connected in a manner to preventmutual interference of the cutting blades and to allow of paralleldisposition of said blades; said tool being adapted for causing its bitsto rotate by reciprocating the cable and, by twisting the cable duringreciprocation, to change its angular position in the drill hole forpresenting new drilling areas vto the bits and causing the tool to drilla round hole of larger diameter than the bits,

ALBERT S. BAP'lIE..

